Do-it-yourself repair of ball-bearing turbines

In detail: do-it-yourself repair of ball-bearing turbines from a real master for the site my.housecope.com.

The purpose of writing this article is to acquaint owners, present or future, with ball bearing technology (ballbearing) in turbochargers.

Sleeve turbine:

As you know, in classic sleeved turbines, one of the most loaded parts is the thrust bearing.

It is a bronze plate to which oil for lubrication is supplied and stops or a bobbin, as they call it, which stand on the shaft and, leaning on this plate, keep the shaft from axial movement.

This is necessary so that the impellers of the turbine and compressor do not rub against the turbine housings and do not wear out. With an increase in boost, the turbine shaft begins to experience axial pressure towards the turbine part, respectively, the load on the bearing plate and the stops increase, which at some point cease to withstand the load and begin to wear out.

So the turbine has axial play, which is wear. Over time, wear progresses and at some point the turbine impeller touches the housing blades, such a turbine has only a few days to live.

Any wear is uneven, the shaft is unbalanced, vibration appears and the turbine literally falls apart.

There is another drawback to the bushed turbine, which is the friction inside the turbine cartridge, which results in a later spin-up and more lag.

It is customary to say that the turbine on the bushings is less responsive (spins up more slowly) than the ball one. Another disadvantage of sleeve turbochargers is the pickiness to the quality and purity of the oil, the tendency to coke the oil on the shaft.

Video (click to play).

Another serious disadvantage that little is known about is the large amount of oil needed to create an oil wedge on plain bearings. A large amount of oil tends to leak not into the drain or sump of the engine, but through the shaft seals into the compressor or into the turbine part to the exhaust. This happens from wear and coking of the sealing rings on the turbine shaft.

Almost every sleeved turbine that fell into my hands had oil leaks towards the compressor and turbine.

Now consider the design of turbines on ball bearing technology:

In the 1990s, Garrett developed an alternative to its "T" series of turbochargers. By that time, the order of outdated, having an old-fashioned design of the turbine and compressor parts. And also the main disadvantage is the large masses of rotating parts.

It was decided to completely develop a turbine on an angular contact bearing, having completely new turbine and compressor wheels.

The main part of such a turbocharger is a bearing:

It is designed in such a way that there is no longer a need for a thrust bearing, and therefore the rotating masses are reduced and the less friction, the sooner the boost is reached.

The bearing itself consists of inner and outer races of the separator and the bodies of rotation of the balls themselves.

As can be seen from the figure, the bearing is not simple, but thrust, that is, when axial loads are applied, the inner race does not allow the shaft to move to the side and touch the housing, grease is also supplied to the bearing through special holes

A new compressor (photo) and turbine wheel with a more open blade profile was specially developed for this turbocharger (GT X series, and later GTX R series)

Thanks to this, the gases began to flow more freely, the back pressure dropped and it was possible to reduce the size of the turbine part at the same power.

All this, together with a redesigned compressor, allowed us to increase productivity by 15%, as well as make the response faster.

This is felt as a decrease in the reaction time to the gas pedal and an increase in torque in the zone of low crankshaft speeds. Many drivers who drive such vehicles have admired the excellent throttle response and the fast, almost instantaneous increase in power.

Another plus of such turbines is that the oil is supplied to the cartridge through a special jet (restrictor) with a selected section, due to which the oil is supplied exactly as needed to lubricate the bearing.

I think it’s not worth saying that such turbines practically do not let oil through.

However, it was not without a fly in the ointment - the bearing has a number of design flaws. (Consciously or not - we will omit this, now it's not about that).

Bearing cages are literally made of plastic. The author knows cases when they melted with an increase in EGT (exhaust temperature). The consequences are sad - balls without support begin to fall out of the tracks, the shaft begins to hang out, cling to the impeller housing, the seals are worn off and the entire turbine becomes unusable.

Also, separators fall apart from banal pops into the muffler when fuel is overflowed, and also simply from old age.

In general, the assembly turned out to be quite reliable (withstands high boosts) and unreliable (there is a chance of damage to the plastic separator and failure of the turbine).

Although designs from other manufacturers are known, where there are no such shortcomings. The clips are made of bronze, and there is a spacer spring, the purpose of which is to burst the clips, thereby choosing the backlash from this unit. Such a node is quite reliable in itself, but the turbine in which it is installed has a number of other disadvantages, which will be discussed in a separate article.

The authors of this project have accumulated extensive experience in studying the design and increasing the service life of ball bearing turbines.

For many car enthusiasts who love power and speed, the issue of buying a car with a turbocharged engine is very important.

In turn, the task of the turbocharger is to supply more air to the engine cylinders and, as a result, increase the power of the latter.

The only drawback of such a useful element is frequent failure, so every motorist should be able to make at least minimal turbine repairs.

Structurally, a turbocharger is a very simple mechanism that consists of several main elements:

The common body of the node and the snail;
Plain bearing;
thrust bearing;
Distance and thrust sleeve.

The turbine housing is made of aluminum alloy, and the shaft is made of steel.

Therefore, in the event of failure of these elements, the only right decision is only replacement.

Most turbine damage can be easily diagnosed and repaired. At the same time, you can entrust the work to professionals in their field or do everything yourself.

In principle, there is nothing complicated about this (we will consider how to dismantle and repair a turbine in the article).

As the practice of operation shows, in total there are two main causes of breakdowns - poor-quality or untimely maintenance.

If, according to the plan, a technical inspection is carried out, then the turbine will work for a long time and without any complaints from motorists.

So, for today, there are several main signs and reasons for the failure of the turbine:

1. The appearance of blue smoke from the exhaust pipe at the time of the increase in speed and its absence when it reaches the norm. The main reason for such a malfunction is oil entering the combustion chamber due to a leak in the turbine.

2. Black smoke from the exhaust pipe - indicates the combustion of the fuel mixture in the intercooler or injection line.The probable cause is damage or breakdown of the TKR control system (turbocharger).

3. Smoke from the exhaust pipe of white color indicates clogging of the turbine oil drain line. In such a situation, only cleaning can save.

4. Excessive oil consumption up to one liter per thousand kilometers. In this case, you need to pay attention to the turbine and the presence of a leak. In addition, it is advisable to inspect the joints of the pipes.

5. Dynamics of dispersal "blunted". This is a clear symptom of a lack of air in the engine. The reason is a malfunction or breakdown of the TKR control system (turbocharger).
6. The appearance of a whistle on a running engine. The likely cause is an air leak between the motor and the turbine.
7. A strange rattle during turbine operation often indicates a crack or deformation in the assembly housing. In most cases, with such symptoms, TCR does not “live” for a long time, and further repair of the turbine may be ineffective.

8. Increased noise in the operation of the turbine can cause clogging of the oil pipeline, changing the gaps of the rotor and touching the latter on the turbocharger housing.
9. An increase in exhaust emissions or fuel consumption often indicates problems with the air supply to the TKR (turbocharger).

To repair the turbine with your own hands, it must be dismantled.

This is done in the following sequence:

1. Disconnect all pipelines that go to the turbine. In this case, you should be extremely careful not to damage the node itself and the devices adjacent to it.

2. Remove the turbine and compressor volutes. The latter is dismantled without problems, but the turbine volute is often attached very tightly.

Here, dismantling can be done in two ways - using a mallet method or using the snail mounting bolts themselves (by gradually releasing them from all sides).

When performing work, you must be very careful not to damage the turbine wheel.

3. Once the work of dismantling the volutes is completed, you can check for shaft play. If the latter is missing, then the problem is not in the shaft.

Again, a little lateral play is acceptable (but no more than one millimeter).

4. The next step is to remove the compressor wheels. Pliers will come in handy for this job. When dismantling, please note that the compressor shaft in most cases has a left-hand thread.

To dismantle the compressor wheel, a special puller is useful.

5. Next, the sealing inserts are dismantled (they are located in the recesses of the rotor), as well as the thrust bearing (it is mounted on three bolts, so there are no problems with removal).

6. Now you can remove the liners from the end part - they are fastened with a retaining ring (during dismantling, sometimes you have to tinker).

The plain bearings (compressor side) are fixed with a circlip.

7. When performing dismantling work, it is necessary (regardless of the breakdown) to thoroughly rinse and clean the main elements - the cartridge, seals, rings and other components.

Once the dismantling is completed, repairs can be made. For this, a special repair kit should be at hand, where there is everything you need - liners, hardware, seals and rings.

Check the quality of fixation of nominal inserts. If they hang out, then they need to be machined and the shaft balanced.

In this case, it is advisable to clean the liners well and lubricate with engine oil.

The retaining rings located inside the turbine must be installed in the cartridge. At the same time, make sure that they are in their place (in special grooves).

After that, you can mount the turbine liner, after lubricating it with engine oil. The insert is fixed with a retaining ring.

The next step is to install the compressor liner, after which a well-lubricated bushing can be inserted.

Next, put a ring plate on it and tighten it well with bolts (without fanaticism).

Install the dirt plate (secured with a circlip) and oil scraper ring.

It remains only to return the snail to its place. That's all.

This article indicates the general algorithm for disassembling and assembling a turbine. Of course, depending on the type of the latter, this algorithm will be partially changed, but the general course of work will be identical.

Well, if a serious breakdown is detected, then it is better to immediately replace the old turbine with a new one.

In the absence of serious defects, the repair of the turbine takes no more than a few hours. But with the help of improvised tools and material prepared in advance, you can make a very high-quality and budgetary repair.

Installing a turbocharger on a diesel engine increases energy efficiency, torque, power and throttle response of the engine. Long-term operation and untimely maintenance lead to unit failure. If you have locksmith skills and tools, you can repair the turbocharger with your own hands. To do this, you need to study its device and read the repair instructions.

Material content [expand]

The unit consists of three main sections:

hot (turbine), working with exhaust gases;
compressor room supplying compressed air to the manifold;
cartridge (bearing assembly) that transmits torque from the turbine to the compressor impeller.

In the turbine or compressor part there is a control system that controls the action of the bypass valve. The compressor impeller is put on the shaft, which is a continuation of the turbine. Lubrication to the bearings is supplied through oil channels.

Given the not too complicated device and the high cost of the unit, do-it-yourself turbine repair on a diesel engine allows you to save a lot.

The following signs indicate the need for repair:

Increased consumption of oil that enters the cylinders. This may be accompanied by the appearance of blue smoke from the exhaust.
Loss of power due to air entering through the nozzle seals.
Changing the composition of the fuel-air mixture. This is expressed in increased fuel consumption and the appearance of black smoke from the exhaust pipe.
Increased turbine noise due to worn cartridge bearings.

If you notice at least one of the signs, it is time to check the operation of the supercharger and repair the turbine yourself on a diesel engine.

Repairing a diesel engine turbine on your own requires tools, spare parts, and advanced locksmith skills. In their absence, it is cheaper to turn to professionals. Assembly in artisanal conditions can lead to the ingress of grains of sand into the unit. As a result, it will eventually fail. If you are confident in your abilities, you can get to work.

Before you repair the turbine, you should prepare a repair kit. You will need the following details:

You will also need the following set of tools:

socket and open-end wrenches;
screwdrivers;
pliers with sliding jaws;
curly editing;
puller;
mallet.

This is enough to restore the turbine with your own hands.

Do-it-yourself repair of a diesel engine turbine for a passenger car or truck begins with its dismantling. To do this, you need to perform the following operations:

unscrew the bolts or remove the stoppers that fix the housings of the compressor and turbine assembly;
if the knot has become attached, it must be carefully “wakened up” by tapping with a mallet;
remove the snail.

First you need to check the cartridge bearings: the longitudinal play is unacceptable, the transverse play is only very small. AND

The compressor retaining ring is removed using pliers with sliding jaws. The reverse side of the shaft is clamped with curly editing.

When disassembling, do not forget about the left-hand thread on the shaft.

The compressor wheel cannot be removed without a special puller.To prevent unbalance of the assembly, it is necessary to install the parts in the same position during assembly. To do this, mark the wheel and nut.In order to qualitatively repair the turbine with your own hands, you need to carefully clean all the parts and check their condition.Bushing wear is the main cause of cartridge play. To replace them, you need to remove the retaining rings and unscrew the mounting bolts. You will also have to change the liners that are held by the stopper. Before removing the seal rings, clean the carbon deposits from the cartridge shaft and impeller.In the event that shaft wear is noticeable, worn liners of nominal size are replaced with repair ones. The shaft will have to be turned to the repair size and balanced. If the development is only on the liners, you can put new nominal size. This completes the do-it-yourself repair of the supercharger turbine cartridge.After the repair is completed, it remains to assemble the unit and put it in place. Be sure to check the tightness of the retaining rings when installing them on the cartridge. If they do not sit in the nests, the structure will crumble during operation.Bearings, bushings and oil scraper rings of the shaft are lubricated with oil before installation. This ensures that there are no scuff marks at the first start.

The parts are assembled in the reverse order of their removal at the previous stage.

The impeller fastening nut is tightened with a force of 5 N.m, unless otherwise provided by the manufacturer's instructions.

The assembled device is placed on the engine and fixed with screws or stoppers.

They are achieved due to the built-in turbocharger, which supplies large volumes of air to the engine cylinders, thereby increasing its power. However, the happiness of owning such a super-useful unit is overshadowed by its frequent breakdown. All car parts wear out over time, but turbine repair is much less common than a complete replacement of a damaged mechanism.

Compliance with elementary operating rules, a thorough technical inspection on time, the use of high-quality synthetic oil and its regular replacement, the correct position of the oil pipeline without kinks, the presence of a turbo timer and the purchase of a blow-off bypass valve - these simple manipulations can increase the durability of a turbocharger several times.Not everyone can afford the opportunity to visit a service station at the slightest malfunction, so it makes sense to learn the basics of minimal turbine repair on your own.

The turbine circuit is quite simple, its main elements are:

The common body of the node and the snail.
Plain bearing.
Thrust bearing.
Distance and thrust bushings.

Since the main elements of the turbine are metal (aluminum housing, steel shaft), they cannot be repaired - only replaced.

The main causes of turbine failure quite amenable to self-diagnosis and repair. Of course, in the absence of the necessary skills, it is better to entrust these procedures to professionals.

Almost all breakdowns are based on 2 violations: inspection performed poorly or not on time.

When the rpm is increased, blue smoke is emitted from the exhaust pipe, which disappears at normal values.

Cause: There is a leak in the turbine through which oil enters the combustion chamber.

Emission of black smoke from the exhaust pipe.

Cause: The fuel mixture burns out in the intercooler or pressure line when the control system malfunctions.

Cause: Turbine oil drain is impassable and needs to be cleaned.

Increased oil consumption per mileage (can reach a ratio of 1 liter: 1000 km).

Reason: leak in the turbine, separation of the joints of the pipes.

Car acceleration takes longer.

Cause: Decrease in air volumes supplied by the turbocharger due to its malfunction.

Whistle when the engine is running.

Reason: violation of the continuity of the connection between the motor and the turbine, air leakage into the gaps formed.

Grinding sound when the turbine is running.

Reason: most likely deformation of the assembly body, self-repair is ineffective, it may be necessary to replace the entire turbocharger.

Increased noise level when the turbine is running.

Cause: blockage of the oil line, increased rotor clearances, contact between the rotor and the turbocharger housing.

Increased fuel consumption and increased concentration of exhaust gases.

Reason: broken connection to the turbocharger, insufficient air supply.

These include: a pipe that connects the turbine to another pipe to create an air flow.

We remove both snails: turbine (you may need to make an effort) and compressor. We remove it either with the help of a mallet - knock it down, or unscrew the attaching bolts. We try not to touch the turbine wheel.

It is necessary to carefully examine the condition of the blades. In the presence of surface deformations, even of minimal dimensions, they need to be replaced or repaired by grinding and turning.

We evaluate the condition of the pipe. There may be slight drops of oil on it, but ideally the nozzle should be almost dry. On many turbocharger models, a venting system is attached to its bore. If it is damaged or the parts diverge, there will be a significant amount of oil at the junction, as well as on the pipe itself. In this case, it will not be possible to manage on your own, it is necessary to connect professionals to the repair.
We check the serviceability of the shaft - after removing the snails, we look for the presence of play - we grab the shaft with our hand and try to shift it in the direction of the axis. Half- and one-millimeter lateral play is quite acceptable. We also immediately check the radial play - the blades touching the turbine housing: we rearrange the shaft to the extreme right state and turn the blades. When these parts come into contact, the situation indicates the need to replace the turbine due to a breakdown. It is necessary to disconnect the pipe from the intake manifold or intercooler and the turbine and evaluate the condition of the holes.If a significant amount of oil is noted in the pipe, but there is practically no oil in the area of the holes, we conclude that the turbocharger is malfunctioning, accompanied by an increased oil consumption above the maximum value.
We remove the compressor wheels with the help of pliers and a special puller, while remembering the left-hand thread on the compressor shaft.
We separate the sealing inserts in the cavities of the rotor and unscrew the 3 bolts of the thrust bearing.
We separate the sealing inserts from the retaining ring from the end of the turbine.
We remove the plain bearings, also fixed on the retaining ring on the compressor side.
The main components, such as the cartridge, seals, rings, etc., should be cleaned and washed during disassembly.
Pay attention when buying a vehicle: the presence of a luminous inscription of the Check-engine indicator on the panel means a serious malfunction of the turbine. Only an expert can determine the exact cause of the breakdown in the case.

It is necessary to have a special repair kit available, which includes hardware, rings, seals and liners.
We check the fixedness of the nominal inserts. If there are fluctuations, we grind, clean, lubricate with engine oil and balance the shaft.
Retaining rings are installed in special grooves of the cartridge inside the turbine.
Lubricate the turbocharger liner with special engine oil and fix it in place with the retaining ring.
Install the compressor insert.
Lubricate and install the bushing.
From above, we fix the sleeve with a plate due to bolts.
We install protection against dirt with the help of retaining rings.
Install the oil seal ring.
We install snails.

You should be very careful with dismantled turbine assembly. Often a situation arises when the analysis went quite well, but there are problems with the installation. Thoroughly cleaned of dirt, washed with a specially selected composition and examined for deformations (if necessary, they are replaced), the turbine parts are very carefully, until they stop, installed in the intended grooves.

Structural feature of the turbine - a small number of elements determines its relative durability. Its components are easily amenable and in most cases require replacement, but even if absolutely all parts fail, the turbine is able to perform work. However, this fact should not be taken as a guide to action, as a malfunctioning turbine provides a truly fantastic oil consumption.

The specified sequence of operations is common for all types of turbochargers, depending on the model, some actions may vary. In case of a serious malfunction, it is recommended to replace the damaged turbine.

Video (click to play).

To save money, it makes sense to master the independent repair of the turbine, especially considering that the time costs do not exceed several hours.